There are known ways, especially for companies engaged in distance-selling and dispatching of products in small volumes, of implementing package-preparing systems. The term “package” is understood to mean an object or a set of goods comprising several objects, regardless of weight, dimensions and volume, constituting a unit load, because it is packed (in tubs, boxes, cases or crates, cardboard boxes, containers, overwraps, strapped or film-wrapped pallets, etc.).
The main examples of users of these automated or semi-automated systems for preparing orders are suppliers for large-scale distribution (fresh and dry goods for example), office equipment, clothing, cosmetics, tools and spare parts in the engineering sector. These systems enable preparation, with minimum labor force and within a set lead time, of a dispatch unit, corresponding to a precise order (also called a “customer order”) from a customer, the order relating to several packages (otherwise called unit loads or goods) in different quantities, each of the packages with its quantity being identified by an order line.
These order-preparing systems generally implement a sorting system comprising for example an automated sorting and storage depot or a “cross-docking” type of order-preparing platform.
Cross-docking is an operation that makes it possible to consolidate the unit loads according to customer order from a sorting platform such as a sorting carousel. This technique makes it possible to prepare an order without in any way relying on a warehouse. It is therefore not necessary to store goods to carry out an order preparation or picking, of the unit loads ordered. The unit loads delivered, for example by supplier's vehicles, are deposited directly or indirectly on a sorting system to be sorted according to order. Unit loads can then be picked up one by one to be repacked.
One drawback of the cross-docking technique is that, despite its advantage in terms of reactivity and storage costs, it entails relative constraints in terms of logistics, i.e. with regard to the means needed for transporting and routing the flows of unit loads. Indeed, since the unit loads pass one by one, substantial conveyance means are needed, leading to relatively high costs.
Another drawback is that the floor space occupied by these different means implemented proves to be relatively great, and this is not satisfactory either.
Yet another drawback is that the time taken to prepare an order proves to be relatively great because of the lead time for taking each of the unit loads up to its destination (a repacking station for example) and hence because of the flow generated.
These drawbacks also exist for automated sorting and storage depot type sorting systems.